Adhesive patch

ABSTRACT

An adhesive patch for covering a portion of the anatomical surface of a living being, said patch being able to adhere to the skin, and/or a wound on a part of the body, said patch comprising a backing layer and a layer of a skin-friendly adhesive for adhering to the skin, and said patch having a pattern of indentations wherein the indentations are in the form of a pattern of curvilinear indentations shows a flexibility capable of adapting to the contour of a skin surface or a joint that is frequently bent ensuring a snug fit and a safe grip.

This is a nationalization of PCT/DK2004/000203 filed 24 Mar. 2004 andpublished in English.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to adhesive patches suitable for use fordressings, such as medical dressings for covering a portion of theanatomical surface of a living being, or, in particular, for use asadhesive barrier member for ostomy appliances, a method for preparingsuch adhesive patches, and methods of treating a portion of theanatomical surface of a living being, especially a protruding part ofthe body, and for applying an ostomy appliance comprising such adhesivepatch.

In connection with surgery for a number of diseases in thegastrointestinal or urinary tract a consequence is, in many cases, thatthe colon, the ileum or the ureter has been exposed surgically and thepatient is left with an abdominal stoma, or, in nephrostomy orureterostomy, the ureter or a catheter is exposed in the back or thechest region or abdominal region, and the effluents or waste products ofthe body, which are conveyed through these organs, are dischargedthrough the artificial orifice or opening and are collected in acollection bag, which is usually adhered to the skin by means of anadhesive wafer or plate having an inlet opening for accommodating thestoma/ureter/catheter. Also in connection with a fistula, the patientwill have to rely on an appliance to collect the bodily materialemerging from such opening.

Ostomy appliances are well known. Such appliances may be two-piece orone-piece appliances. In both types of appliances, an adhesive barriermember or base plate is attached to the wearers abdomen/back/chest. Incase of a one-piece appliance, a receiving member or bag is attached tothe base plate. In case of a two-piece appliance, the adhesive baseplate forms part of a body side member and a receiving member or bag isattached releasably to the body side member for receiving exudates fromthe stoma.

When using one-piece appliances, the whole appliance, including theadhesive skin barrier securing the appliance to the skin is normallyremoved and replaced by a fresh appliance. When using two-pieceappliances, the body side ostomy member is left in place up to severaldays, and only the receiving member or bag attached to the body sidemember is replaced.

Conventionally, dressings for the treatment or prevention of wounds orpressure sores or even unbroken skin are essentially flat dressings,which are sufficiently mouldable to be applied to flat or slightlycurved areas of the body. Such flat dressings are not very suitable forapplying on protruding parts of the body such as joints e.g. heels orespecially elbows or knees having not only a very pronounced curvaturebut also being subject to constant bending which often causes wrinklingand focusing of stresses in the dressing often causing release of theadhesive and unintended detachment of the dressing.

When an ostomy appliance is placed on the abdomen of a user, the bandagehas to follow the movements of the skin caused by physical activity asthe user would else have a feeling of carrying a very inflexibleproduct, or the appliance might lose its hold of the skin.

The physical activity and change of positions of the user give rise to abending, stretching, or upsetting of the appliance. The first attackwill be concentrated at the borderline between uncovered skin and skincovered by the appliance. When stretching is caused at this borderline,several events/things may happen.

If the appliance is sufficiently flexible, this effect will hardly benoticed by the user. If the flexibility of the appliance is insufficientto take up the stretching, bending and upsetting, and the adhesion tothe skin is maintained, the user will notice the effect and willeventually experience a pain or itching under the appliance. If theadhesion to the skin is broken, the appliance will loosen from the skinand eventually cause a leakage.

2. Description of the Related Art

Flexibility of an ostomy appliance may be obtained in several manners.The appliance may be made very thin and having a flexible carrier sheetbut a very thin layer of adhesive will due to the low mass not show asufficient absorbing capacity to uphold an acceptable service time forthe appliance. If a high absorbing capacity is desired, the thickness ofthe adhesive layer may be increased causing a loss of flexibility of theappliance. In this case one way to preserve the flexibility is toprovide embossing or indentations in the product providing areas inwhich the adhesive layer is thinner. The flexibility is then obtained asthe thinner areas easier yield on applied forces conserving theabsorption capacity of the thicker product.

Thus, WO 93/00056 discloses that a skin-friendly dressing having groovesor ditches fully or partly surrounding a central part of the dressinghas a high degree of flexibility.

EP patent No. 0 768 071 discloses a wound dressing especially for use inthe sacrum area, said dressing having one or more linear depressionsthat assist a user in applying, flexing or folding the dressing and thatthe dressing may have two sets of spaced parallel depressions forming agrid which is useful in the wound assessment. The thickness of theadhesive layer at the base of the depressions should at least be asgreat as the thickness of the border portion of the adhesive layer.

GB patent No. 1,075,939 discloses an adhesive bandage having athermoplastic top film provided with embossments in order to allowpassage of water vapour though the film.

Published EP patent application No. 0 256 893 discloses a non-adherentdressing comprising a film which contains depressions over the woundcontacting area which depressions contain a viscous pharmaceuticalcomposition which is suitable for topical application. The depressionsmay be in the form of a pattern of conical depressions.

GB patent No. 1,075,939 and EP patent application No. 0 256 893 aresilent with respect to flexibility.

WO 99/36017 discloses a dressing comprising a substantiallywater-impervious layer and a skin-friendly adhesive having a pattern ofindentations, which diminishes or disappears when the dressing ismoisturised. The grooves are stated to have a depth of at least 25% andmore preferred at least 50% of the thickness of the dressing and it isstated that the pattern may increase the flexibility of the dressing.

The publications do not disclose the problems associated with formationof wrinkles or folds during use of a wound dressing or an ostomyappliance, which may lead to formation of canals causing risk of leakingof obnoxious smells or soiling from aggressive exudates.

Furthermore, it has been found that the flexibility of a dressing oradhesive barrier member of an ostomy appliance is important, withrespect to the shape, the size and the adhesive of the dressing, notonly in use but also during the application.

When applying a dressing on a joint that is frequently bent, or whenapplying an ostomy appliance to an uneven of folded abdomen, flexibilitybecomes very important as the dressing or ostomy appliance must be ableto adapt to the contour of the skin surface.

SUMMARY OF THE INVENTION

The invention relates to an adhesive patch for covering a portion of theanatomical surface of a living being, said patch being able to adhere tothe skin, and/or a wound on a part of the body, said patch comprising abacking layer and a layer of a skin-friendly adhesive for adhering tothe skin, and said patch having a pattern of indentations.

The invention also relates to an ostomy appliance comprising an adhesivepatch for covering a portion of the anatomical surface of a livingbeing, said patch being able to adhere to the skin, and/or a wound on apart of the body, said patch comprising a backing layer and a layer of askin-friendly adhesive for adhering to the skin, and said patch having apattern of indentations.

Furthermore, the invention relates to a wound dressing comprising anadhesive patch for covering a portion of the anatomical surface of aliving being, said patch being able to adhere to the skin, and/or awound on a part of the body, said patch comprising a backing layer and alayer of a skin-friendly adhesive for adhering to the skin, and saidpatch having a pattern of indentations.

The invention also relates to a method for preparing a dressingcomprising a backing layer and a layer of a skin-friendly adhesive foradhering to the skin, which dressing has a pattern of indentations.

Still further, the invention relates to a method of treating a portionof the anatomical surface of a living being, especially a protrudingpart of the body.

Yet further, the invention relates to a method for applying an ostomybody side member or a one-piece ostomy appliance comprising an adhesivepatch for covering a portion of the anatomical surface of a livingbeing, said patch being able to adhere to the skin, around a stoma, saidpatch comprising a backing layer and a layer of a skin-friendly adhesivefor adhering to the skin, and said patch having a pattern ofindentations.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention is disclosed more in detail with reference to the drawingsshowing an embodiment of an adhesive patch of the invention.

DETAILED DESCRIPTION OF THE PRESENT INVENTION

The present invention relates to an adhesive patch for covering aportion of the anatomical surface of a living being, said patch beingable to adhere to the skin, and/or a wound on a part of the body, saidpatch comprising a backing layer and a layer of a skin-friendly adhesivefor adhering to the skin, and the patch further comprising a firstcentral area of a relatively high thickness, a second area surroundingthe first area, and a third edge area surrounding the second area, saidthird area has a pattern of indentations, wherein the indentations arein the form of a pattern of curvilinear indentations.

It is preferred that the indentations do not form angles with the borderof the patch of 90° and 180°.

An adhesive patch comprising a network of indentations in which thelines form angles with the border of the patch of 90° and 180°,respectively, provides a flexible structure, but an attack by a forceperpendicular to the border could relatively easy produce a bendperpendicular to the border, which may cause the patch to loosen. Thiseffect is counteracted by the curvilinear indentations present in theborder area of a patch of the invention wherein the indentations do notform angles with the border of the patch of 90° and 180°.

In one embodiment of the invention, the patch comprises a first centralarea of a relatively high thickness; a second area surrounding the firstarea, and a third edge area surrounding the second area wherein thefirst area is provided with a pattern of indentations and the third areais provided with a pattern of curvilinear indentations. In thisembodiment, the second area may assist in stopping the propagation ofwrinkles or folds from the edge or from a centre hole of the patch.

In another embodiment of the invention the indentations in the firstarea comprises a set of “radial” indentations providing flexibilityperpendicular to the indentations. The term “radial” as used in thepresent context is intended not only to comprise directions from thecentre of a circle towards the periphery but also to comprise notcrossing directions from a central part of e.g. an ellipse or anotherclosed figure towards the periphery thereof.

In a further embodiment the first area comprises set of indentationsencircling the central part. Indentations of this kind are preferablypresent together with and crossing a set of radial indentations andprovide providing a markedly increased flexibility in the central areaof the patch and counteracts a stiffening or enforcing effect providedby a set of radial indentations.

In a further embodiment of the invention wherein the indentations in thethird area are in the form of two or more series of curvilinearindentations crossing each other a very high degree of flexibility isobtained in the border area between free skin and neighbouring skincovered by the patch and furthermore does not provide straight linesfacilitating the progressing of a wrinkle or fold. This embodiment isbelieved rather to deflect such progressing wrinkles or folds reducingthe risk of causing a leak.

In yet a further embodiment the indentations are in the form of grooveshaving a level bottom. The presence of a level bottom of theindentations improves the flexibility and capacity for taking uppropagating wrinkles or folds in a level where the damage caused by thewrinkles or folds is kept barely noticeable and also to be able toabsorb the effect of larger folds.

It has been found suitable when the width of the indentations, is in themagnitude of from about 0.5 to about 3 millimetres, e.g. 1-2millimetres, suitably 1.2 millimetres providing a suitable flexibility.It is suitable when the width of a level at the bottom of theindentations is of the same order of magnitude as the stated for thewidth above.

In order to ensure a suitable flexibility of the patch it is preferredthat the indentations have depth of at least two thirds of the totalthickness of the patch. In accordance with a preferred embodiment theindentations have depth of at least 75% of the total thickness of thepatch, more preferred up to 90% and even exceeding 90% of the totalthickness of the patch. Thus, the patch may be considered as a number ofthick parts connected by thinner bridging parts. The bridging parts arepreferably sufficiently large and present in a sufficient number toallow stress originated from movement to be relaxed without proceedingfrom one thick part to the next.

The curvilinear indentations, when the patch of the invention is seenfrom above, may suitably be defined by a mathematical function of secondor higher order or a hyperbolic function. Such functions give rise tocurvilinear patterns such as circles or super-circles, ellipses orsuper-ellipses, hyperboles and parables or parts thereof.

In a suitable embodiment of the invention the third area is providedwith radial zones having a thickness comparable with the thickness ofthe material in the bottom of the indentations in the third area. Suchzones are suitably without indentations. The presence of such zones atthe border of the patch provides folding zones capable of absorbing alocal high degree of bending caused e.g. when an ostomate is in sittingposition and thus prolong the service time of the patch.

In one embodiment the invention relates to an ostomy appliancecomprising an adhesive patch of the invention, said patch being able toadhere to the skin, said patch comprising a backing layer and a layer ofa skin-friendly adhesive for adhering to the skin, and said patch havinga pattern of indentations wherein the patch comprises a first centralarea of a relatively high thickness and a hole for accommodating astoma, a second area surrounding the first area for attaching acollecting bag or a coupling device, and a third edge area surroundingthe second area, wherein the first and third areas are provided withindentations and wherein the indentations in the third area are in theform of a pattern of curvilinear indentations.

An ostomy appliance according to the invention may be in the form of abody side member or in the form of a one-piece ostomy appliancecomprising an adhesive patch of the invention. A body side membercomprises a coupling means known per se for releasable attachment of areceiving bag.

A skin-friendly adhesive may be any skin-friendly adhesive known per se,e.g. an adhesive comprising hydrocolloids or other moisture absorbingconstituents for prolonging the time of use. The adhesive may e.g. be ofthe type disclosed in those disclosed in U.S. Pat. Nos. 4,367,732,5,051.259, 5,714,225, 6,171,594, 6.303,700, 6,451,883, or 6,437,038, orin WO Application Nos. 00/54820, or 01/05340.

A protective cover or release liner may for instance be siliconizedpaper. It does not need to have the same contour as the patch, e.g. anumber of patches may be attached to a larger sheet of protective cover.The protective cover is not present during the use of the patch of theinvention and is therefore not an essential part of the invention.

The outer periphery of a patch of the invention is preferably bevelledin analogy with the disclosure of U.S. Pat. No. 4,867,748 or U.S. Pat.No. 5,133,821 in order to reduce the risk of “rolling-up” the edge ofthe dressing reducing the wear-time. The edge is preferably bevelled sothat the thickness adjacent to the edge does not exceed about 30% of themaximum thickness of the dressing; more preferred not exceeding 25% ofthe maximum thickness.

A coupling means may be any system known per se for attaching receivingbags to ostomy body side members and may suitably be matching couplingrings of the type disclosed in WO 93/18725, WO 94/18919, WO 91/01118, WO91/01119 or matching flanges for adhesive connection of the typedisclosed in U.S. Pat. No. 5,800,415, WO 00/30576, or WO 01/54632.

A collection bag may be made in analogy with and from materialsconventionally used for the preparation of ostomy appliances. Suchmaterials are suitably films composed of any suitable material, which isheat sealable and sufficiently impervious for unpleasant odours such aspolyolefin films or combinations of such films, e.g. polyethylene or aco-extrudate of polyethylene and polyvinylidene chloride. Suitably thebag is made from front and rear walls welded in a manner known per sealong the rim forming a bag. When cutting or punching the walls, anopening for receiving a stoma is suitably also punched in the wall toform the rear wall.

A collecting bag or a coupling device may be attached to the second zoneusing an adhesive or by welding in a manner known per se.

In another embodiment, the invention relates to a wound dressingcomprising an adhesive patch of the invention, said patch being able toadhere to the skin, said patch comprising a backing layer and a layer ofa skin-friendly adhesive for adhering to the skin, and said patch havinga pattern of indentations wherein the patch comprises a first centralarea of a relatively high thickness, optionally a second areasurrounding the first area, and a third edge area surrounding the firstor second area, wherein the first and third areas are provided withindentations and wherein the indentations in the third area are in theform of a pattern of curvilinear indentations.

A wound dressing of the invention may in one embodiment of the inventionbe in the form of a mono-phase adhesive, i.e. made from one adhesivecomponent or in accordance with another embodiment of the invention bein the form of a two-zone adhesive, e.g. of the general type disclosedin U.S. Pat. No. 5,714,225, i.e. a part of or all of the adhesive areasof the dressing being constituted by more than one type of adhesive.

The backing layer may be made from any suitable thermoplastic materialknown per se for use in the preparation of wound dressings or ostomyappliances e.g. foam, a non-woven layer or a polyurethane, polyethylene,polyester or polyamide suitable for attachment of a collecting bag orcoupling means using an adhesive or by welding.

The backing layer of the patch may e.g. be a water impervious layer orfilm may be of any suitable material known per se for use in thepreparation of wound dressings e.g. a foam, a non-woven layer or apolyurethane, polyethylene, polyester or polyamide film. In accordancewith the invention it has been found in practice that when using athinner backing layer or film than is normally used when preparingmedical dressings, an improved stretchability and adaptability isobtained at the same time as the modulus is reduced. These propertiesare obtained using the same load of adhesive as is conventionally used,and thus, the conventional properties of the adhesive are retained asopposed to the case in which the load of adhesive was lowered giving arisk of insufficient absorbing capacity.

The water impervious layer or film is preferably a low-friction flexiblepolymer film reducing the risk of unwanted stress in an exposed area. Asuitable material for use as water impervious layer is a filmconventionally used as backing layer in the preparation of wounddressings, suitably having a thickness of about 30 microns.

An especially suitable material for use as a water impervious film is apolyurethane film. A preferred low friction film material is disclosedin U.S. Pat. No. 5,643,187.

A dressing of the invention may preferably be sterilised for avoidingthe risk of causing infections when applied to skin areas having brokenskin.

The invention also relates to a method for preparing an adhesive patchfor covering a portion of the anatomical surface of a living being, saidpatch comprising a backing layer and a layer of a skin-friendly adhesivefor adhering to the skin, and said patch having a pattern ofindentations wherein the indentations are in the form of a pattern ofcurvilinear indentations, which method comprises providing a supply ofpatches comprising a backing layer and a layer of skin friendlyadhesive, placing the patches in a press together with a mould having asurface corresponding to the desired pattern of indentations andproviding a sufficient pressure to provide the desired pattern ofindentations. The method may be carried out in a manner known per se andmay be carried out in a stepwise manner or in a continuous manner asfound appropriate. The materials for making a mould and the processconditions may be established by the skilled in the art by routine workconsidering the intended use, e.g. for covering wounds, for protectionagainst abrasion or for ostomy appliances for use after colostomy,ileostomy, or nephrostomy or ureterostomy.

Still further, the invention relates to a method of treating a portionof the anatomical surface of a living being, especially a protrudingpart of the body comprising applying a dressing for covering the portionof the anatomical surface of a living being, said dressing comprising anadhesive patch for covering a portion of the anatomical surface of aliving being, said patch being able to adhere to the skin, around astoma, said patch comprising a backing layer and a layer of askin-friendly adhesive for adhering to the skin, and said patch having apattern of indentations wherein the indentations are in the form of apattern of curvilinear indentations said method comprising locating theportion to be covered, adapting the curvature of the dressing for betterfitting the anatomical surface to be covered, and bringing the adhesivepatch to seal against the skin in the area to be covered.

Yet further, the invention relates to a method for applying an ostomybody side member or a one-piece ostomy appliance comprising an adhesivepatch for covering a portion of the anatomical surface of a livingbeing, said patch being able to adhere to the skin, around a stoma, saidpatch comprising a backing layer and a layer of a skin-friendly adhesivefor adhering to the skin, and said patch having a pattern ofindentations wherein the indentations are in the form of a pattern ofcurvilinear indentations and a hole for receiving a stoma, said methodcomprising locating the stoma, optionally adapting the size of the holeto the stoma, aligning the stoma and the hole of the adhesive patch,placing the body side member or ostomy appliance with the stomaprojecting into the hole of the wafer, adapting the curvature of thepatch for better fitting the anatomical surface neighbouring the stoma,and bringing the adhesive patch to seal against the abdomen of theostomate around the stoma.

Description of the Preferred Embodiments

The invention is now explained more in detail with reference to thedrawings showing a preferred embodiment of the invention.

In the drawings is shown a preferred embodiment of an adhesive patch Ifor use for an ostomy appliance, said patch being able to adhere to theskin, said patch comprising a backing layer 2 and a layer of askin-friendly adhesive for adhering to the skin, and said patch having apattern of indentations wherein the patch comprises a first central area3 of a relatively high thickness and a central hole 4, a second area 5surrounding the first area for attaching a collecting bag or a couplingdevice, and a third edge 6 area surrounding the second area, wherein thefirst and third areas are provided with indentations 7,8 and wherein theindentations 8 in the third area are in the form of a pattern ofcurvilinear indentations. This embodiment is further provided withradial zones in the third area, said zones 9 having a thicknesscomparable with the thickness of the material in the bottom of theindentations in the third area and the backing layer 2 is provided withan ear 10 protruding from the rim of the patch for an easy grip.

1. An adhesive patch for covering a portion of the anatomical surface ofa living being, said patch being able to adhere to the skin, and/or awound on a part of the body, said patch comprising a backing layer and alayer of a skin-friendly adhesive for adhering to the skin, and thepatch further comprising a first central area of a relatively highthickness, a second area surrounding the first area, and a third edgearea surrounding the second area, said third area has a pattern ofindentations, wherein the indentations are in the form of a pattern ofcurvilinear indentations.
 2. A patch as claimed in claim 1 wherein thefirst area is provided with a pattern of indentations.
 3. A patch asclaimed in claim 1 wherein the pattern of indentations in the first areacomprises radial indentations.
 4. A patch as claimed in claim 1 whereinthe first area comprises a set of indentations encircling the centralpart.
 5. A patch as claimed in claim 1 wherein the indentations in thethird area are in the form of two or more series of curvilinearindentations crossing each other.
 6. A patch as claimed in claim 1wherein the indentations are in the form of grooves having a levelbottom.
 7. A patch as claimed in claim 1 wherein the curvilinearindentations are defined by a mathematical function of second or higherorder or a hyperbolic function.
 8. A patch as claimed in claim 1 whereinthe third area is provided with radial zones having a thicknesscomparable with the thickness of the material in the bottom of theindentations in the third area.
 9. An ostomy appliance comprising anadhesive patch as claimed in claim 1, said patch being able to adhere tothe skin, said patch comprising a backing layer and a layer of askin-friendly adhesive for adhering to the skin, and said patch having apattern of indentations wherein the patch comprises a first central areaof a relatively high thickness and a hole, a second area surrounding thefirst area for attaching a collecting bag or a coupling device, and athird edge area surrounding the second area, wherein the first and thirdareas are provided with indentations and wherein the indentations in thethird area are in the form of a pattern of curvilinear indentations. 10.A wound dressing comprising an adhesive patch as claimed in claim 1,said patch being able to adhere to the skin, said patch comprising abacking layer and a layer of a skin-friendly adhesive for adhering tothe skin, and said patch having a pattern of indentations wherein thepatch comprises a first central area of a relatively high thickness,optionally a second area surrounding the first area, and a third edgearea surrounding the first or second area, wherein the first and thirdareas are provided with indentations and wherein the indentations in thethird area are in the form of a pattern of curvilinear indentations.